This invention relates to rimless spectacles wherein cutouts or the like are provided at the edges of the spectacle lenses and attachment members are attached to those cutouts or the like without using rims.
Attention has been drawn in recent years to a rimless type of spectacles (rimless spectacles) because they offer such advantages as a wide field of view and light weight. There are several types of such rimless spectacles, namely a type wherewith the lower circumference of the lens is suspended by a nylon thread, a type wherewith holes for machine screws are made all the way through the lenses and the frame is secured by machine screws passed through these holes (called two-point or three-piece type), and the PinFeel type wherewith holes are made in the lens edge surfaces, but not all the way through, and pin-like projections in spectacle lens holding members are inserted therein and secured thereto.
Each of the types of rimless spectacles described above has its own respective features. However, these are not necessarily fully satisfactory in view of the machining costs involved and the fact that it is not necessarily easy to effect the design for lenses of various thicknesses and various materials which adequately realize wide effective field of view, durability, aesthetic attractiveness, and lighter weight, etc.
That being so, in recent years a type of rimless spectacles has been proposed that is designed so that cutouts or the like are provided at the edges of the spectacle lenses and attachment members are fit into those cutouts or the like and attached. Such types of rimless spectacles known to the prior art include those described in Japanese Patent No. 2997438 (Patent Application Laid-Open No. H10-228000/1998)) and Japanese Utility Model Registration No. 2602605 (Utility Model Application Laid-Open No. H7-32620).
The rimless spectacles described in Japanese Patent No. 2997438 (Patent Application Laid-Open No. H10-228000/1998) are based on a structure wherein cutouts (=fastening indentations 10) are provided in the lenses, channels (=insertion channels 20) are provided in attachment members (=end pieces 2) which fit into those cutouts, those channels (=insertion channels 20) are fit into the cutouts (=fastening indentations 10), and the wall portions on both sides of the channels abut on the front and back surfaces of the lenses and are thus secured (cf. FIG. 2 in the publication cited), whereupon the attachment members (=end pieces 2) are attached to the lenses.
What is characteristic in the rimless spectacles described in Japanese Utility Model Registration No. 2602605 (Utility Model Application Laid-Open No. H7-32620) is that the cutouts or channel-shaped portions provided in the lenses are made with a structure xe2x80x9cwherein channels are provided of a shape having a wide part having a greater width than the opening partxe2x80x9d so that the shapes of those cutouts or channel-shaped portions becomes a so-called end-broadening shape.
However, the rimless spectacles described in Japanese Patent No. 2997438 (Patent Application Laid-Open No. H10-228000/1998) suffer a shortcoming in that, insofar as the thickness of the lenses is subject to various changes according to the layout or lens power required by the wearer, the width of the channels (=insertion channels 20) in the attachment (=end pieces 2) must also be changed to match that lens thickness, which is troublesome. Furthermore, because the width of the attachment members (=end pieces 2) must always be made greater than the width of the cutouts in the lenses, they will always protrude from the front and back surfaces of the lenses, so that the field of view will be narrowed by that amount and aesthetic attractiveness impaired.
With the rimless spectacles described in Japanese Utility Model Registration No. 2602605 (Utility Model Application Laid-Open No. H7-32620), on the other hand, the attachment members must be fashioned into a shape wherewith they can be fitted into the xe2x80x9ccutouts of end-broadening shape,xe2x80x9d wherefore the root portions thereof must of necessity be formed narrower than the end-broadened tip end portions. These root portions, however, must have sufficient strength to support the temples or the like that are joined to these attachment parts, wherefore the thickness needs to be greater than prescribed. Thereupon, the portions of end-broadening shape described earlier must be made even thicker than the thickness noted earlier, the lenses will have to be greatly cut out, the field of view will be narrowed, and the aesthetic appearance will be impaired, wherefore this leads to shortcomings. The machining involved in providing the cutouts of end-broadening shape is not easy either.
The structure of conventional rimless spectacles, including those described in the publications noted above, furthermore, is such that, as in conventional ordinary rimmed spectacles, end pieces are provided in the attachment parts, and hinges are provided in those end pieces so that the temples can be folded over. There are therefore limits on effecting lighter weight and improving the aesthetic appearance, etc.
An object of the present invention is to provide rimless spectacles that can be easily manufactured, wherewith a wide effective field of view, durability, aesthetic appearance, and lighter weight, etc., can easily be secured.
First means for resolving the problems described in the foregoing are rimless spectacles which are designed so that cutouts are provided in the edges of the spectacle lenses and attachment members are fit into those cutouts and attached without using rims, wherein the cutouts and attached without using rims, wherein the cutouts have widths that are either substantially constant or gradually narrow from the edges of the spectacle lenses toward the centers thereof, and have ridges, substantially parallel to the front and back surfaces of the spectacle lenses, formed in the inner circumferential walls thereof; the attachment members have grooves formed therein which, when the attachment members are inserted and pushed into place in the cutouts from the edge sides of the spectacle lenses, fit over the ridges in the cutouts where the attachment pieces abut on the inner circumferential walls of the cutouts; and the attachment members are attached to the cutouts by inserting the attachment members into the cutouts from the edge side of the spectacle lenses and pushing them into place so that the grooves in the attachment members fit over the ridges in the cutouts.
Second means are rimless spectacles which are designed so that cutouts are provided in the edges of the spectacle lenses and attachment members are fit into those cutouts and attached without using rims, wherein the cutouts have widths that are either substantially constant or gradually narrow from the edges of the spectacle lenses toward the centers thereof, and have grooves, substantially parallel to the front and back surfaces of the spectacle lenses, formed in the inner circumferential walls thereof; the attachment members have ridges formed therein which, when the attachment members are inserted and pushed into place in the cutouts from the edge sides of the spectacle lenses, fit into the grooves in the cutouts where the attachment pieces abut on the inner circumferential walls of the cutouts; and the attachment members are attached to the cutouts by inserting the attachment members into the cutouts from the edge side of the spectacle lenses and pushing them into place so that the ridges in the attachment members fit into the grooves in the cutouts.
Third means are rimless spectacles according to the first or second means wherein the widths of the attachment members are either substantially equal to or smaller than the widths of the cutouts.
Fourth means are rimless spectacles according to the first, second, or third means, wherein the cutouts constitute shapes such that at least one or other of the front and back surfaces of the spectacle lens is closed.
Fifth means are rimless spectacles comprising attachment structures for directly attaching attachment members to the edges of the spectacle lenses without using rims, in which hinge structures are provided in those attachment members so that the temples can be attached such that the temples can be folded over; wherein the attachment members do not have end pieces extending in directions substantially orthogonal to the front and back surfaces of the spectacle lenses, but hinge structures are formed directly at the sites where the attachment members are attached to the spectacle lenses and the temples are attached such that they can be folded over.
Based on the first to fourth means described above, when the attachment members are pushed into place in the cutouts and attached, they are secured by fitting grooves or ridges provided in the attachment members onto or into ridges or grooves provided in the cutouts, wherefore this securing is made strong. Compared to when the securing is done using screws or the like, moreover, the possibility of loosening after attachment can be made extremely slight. The securing contact surfaces (bonding surfaces) can be made large, wherefore strong attachment can be maintained. At the same time, the attachment members can be formed so that their size is more or less the same as the size of the cutouts. And, because the attachment members can be made flat with the lens faces, without protruding out from the lens faces, an enormous aesthetic advantage is gained, and it becomes extremely easy to wipe the lens surfaces. In addition, the attachment members can be made smaller in size, so the effective field of view can be made wider. Also, because the cutouts have widths that are the same or that become gradually smaller from the lens edges, machining is simplified and automation is easy. It is only necessary to effect a structure wherewith grooves or ridges provided in the attachment members can be pushed into place onto or into ridges or grooves provided in the cutouts, wherefore the lens thickness will have little influence, and there is no problem whatever with making the material thickness of the lens edge either thin or thick. That being so, Ophthalmic use of the spectacles is extremely easy. It is easy to make the attachment structure inconspicuous, and there is no sense of incongruity in terms of design. Due to the securing structure, it is possible to effect strong attachment using various kinds of materials, so those materials are not limited.
Based on the fifth means, moreover, hinges can be deployed directly on the attachment members and the temples attached directly so that they can be folded over without providing end pieces. Thus it is possible to effect new and extremely revolutionary designs never seen before.